Water is the number 1 enemy of the structure of a chimney and it can cause many unwanted and costly damages. Thankfully, most chimney water leaks are easy to diagnose and rectify.
We will start at the top and work our way down to some potential reasons for water leaking through your fireplace or furnace chimney:
No rain cap or top mounted energy-saving damper: When you don’t have a rain cap or an improper one, that allows for water, snow and all other weather elements to simply pour down the flue, slowly destroying it. This can go unnoticed for years, unless you have your chimney inspected by a professional. But even with a chimney cap, you can get certain amounts of rain and snow down into your fireplace flue, simply if the wind drives it horizontally. The best way to stop weather penetration would be to put an energy-saving top-mounted damper on top of your flue or termination tile. These completely seal out all rain, snow and other unwanted elements; including squirrels, raccoons and birds.
Chimney Crown or Chimney Wash: This is the concrete that is poured on top of your bricks, it’s purpose is to protect the brick and mortar joints below it. When poured and formed correctly, these generally will last years – but; even they are not immune to Chicago weather. Eventually small cracks will form and as soon as that starts, it’s basically the beginning of the end – unless you have maintenance done to prevent any further cracking, pitting or deterioration. Some people use a simple caulk to try fixing this problem but it does not work for long and all it takes is one tiny spot to be missed for the attempt to be useless. Windy Chimney uses a tried and true method which is commonly known as Crown Coat and when this is applied correctly, you will have many more worry-free years. Read more about it in our products/crown coat section.
Chimney Flashing: Chimney flashings are the metal that should lay below the shingles of your roof and at the base of your chimney. See image below.
Above are the main causes of water damage to both the chimney and the interior of the home. There are other causes such as an oversized liner which allow for furnace and water heater gases to cool and condensate, literally eating away at your chimney from the inside out. The best route to prevent costly repairs is to have a professional and experienced Windy Chimney technician come inspect all components of your chimney system.